Beijing - A bridge on a major expressway in central China collapsed Friday, leaving the twisted remains of cars and trucks scattered among the rubble as state media reported at least eight fatalities.

There was confusion over the toll, with the official news agency Xinhua saying eight people were dead and 13 injured after a fireworks-laden truck exploded, sending a long section of the viaduct crashing to the ground.

State-run China National Radio initially said that 26 people had been killed, but the report could not later be found on its website, after local authorities in Henan province called the figure “inexplicable”.

State broadcaster CCTV quoted nearby residents as saying they heard a loud booming noise, although it added the cause of the collapse was unclear and it was not known if the truck exploded before or after the bridge collapsed.

Pictures showed tangled wreckage beneath the bridge, including three upturned trucks with their wheels pointing skywards, as rescue workers in orange uniforms scaled the wreckage.

At least five cars could also be seen. CCTV said on its website that at least 25 vehicles were involved.

A crowd of people peered at the debris through thick hazy fog as another lorry teetered on the mangled edge of the bridge's collapsed section.

A new bridge appeared to be under construction right next to the collapsed section.

The bridge near the city of Sanmenxia is on the G30 expressway, the longest road in China, which stretches for nearly 4,400

kilometres (2,700 miles) from China's western border with Kazakhstan to the eastern Yellow Sea.

It stands 30 metres (yards) above the ground, media reported.

Many of China's roads are packed as the country gears up for its most important holiday, the Lunar New Year, when hundreds of millions of people travel back to their hometowns in what is billed as the world's largest annual human migration.

The season is also a peak period for fireworks producers, as Chinese traditionally buy the explosives to celebrate the festival, which falls on February 10 this year.

According to police statistics, around 70 000 people die and 300 000 more are injured in road accidents every year in China, state media have reported.

China has seen a number of bridge collapses in recent years, which are often blamed on overloading and shoddy construction. One such incident in northeast China last August killed three people. - Sapa-AFP